diff --git a/src/modules/locale/LocaleViewStep.cpp b/src/modules/locale/LocaleViewStep.cpp
index 4b4219751..73efc266f 100644
--- a/src/modules/locale/LocaleViewStep.cpp
+++ b/src/modules/locale/LocaleViewStep.cpp
@@ -120,7 +120,7 @@ LocaleViewStep::fetchGeoIpTimezone()
 
             try
             {
-                YAML::Node doc = YAML::Load( reply->readAll() );
+                YAML::Node doc = YAML::Load( data );
 
                 QVariant var = CalamaresUtils::yamlToVariant( doc );
                 if ( !var.isNull() &&
diff --git a/src/modules/netinstall/NetInstallPage.cpp b/src/modules/netinstall/NetInstallPage.cpp
index 9c16433ec..28c836a79 100644
--- a/src/modules/netinstall/NetInstallPage.cpp
+++ b/src/modules/netinstall/NetInstallPage.cpp
@@ -57,14 +57,6 @@ NetInstallPage::NetInstallPage( QWidget* parent )
     ui->setupUi( this );
 }
 
-bool
-NetInstallPage::isReady()
-{
-    // nothing to wait for, the data are immediately ready
-    // if the user does not select any group nothing is installed
-    return true;
-}
-
 bool
 NetInstallPage::readGroups( const QByteArray& yamlData )
 {
@@ -92,10 +84,13 @@ NetInstallPage::readGroups( const QByteArray& yamlData )
 void
 NetInstallPage::dataIsHere( QNetworkReply* reply )
 {
+    // If m_required is *false* then we still say we're ready
+    // even if the reply is corrupt or missing.
     if ( reply->error() != QNetworkReply::NoError )
     {
         cDebug() << reply->errorString();
         ui->netinst_status->setText( tr( "Network Installation. (Disabled: Unable to fetch package lists, check your network connection)" ) );
+        emit checkReady( !m_required );
         return;
     }
 
@@ -104,6 +99,7 @@ NetInstallPage::dataIsHere( QNetworkReply* reply )
         cDebug() << "Netinstall groups data was received, but invalid.";
         ui->netinst_status->setText( tr( "Network Installation. (Disabled: Received invalid groups data)" ) );
         reply->deleteLater();
+        emit checkReady( !m_required );
         return;
     }
 
@@ -112,15 +108,23 @@ NetInstallPage::dataIsHere( QNetworkReply* reply )
     ui->groupswidget->header()->setSectionResizeMode( 1, QHeaderView::Stretch );
 
     reply->deleteLater();
-    emit checkReady( isReady() );
+    emit checkReady( true );
 }
 
-QList<PackageTreeItem::ItemData> NetInstallPage::selectedPackages() const
+PackageModel::PackageItemDataList
+NetInstallPage::selectedPackages() const
 {
-    return m_groups->getPackages();
+    if ( m_groups )
+        return m_groups->getPackages();
+    else
+    {
+        cDebug() << "WARNING: no netinstall groups are available.";
+        return PackageModel::PackageItemDataList();
+    }
 }
 
-void NetInstallPage::loadGroupList()
+void
+NetInstallPage::loadGroupList()
 {
     QString confUrl(
         Calamares::JobQueue::instance()->globalStorage()->value(
@@ -139,7 +143,15 @@ void NetInstallPage::loadGroupList()
     m_networkManager.get( request );
 }
 
-void NetInstallPage::onActivate()
+void
+NetInstallPage::setRequired( bool b )
+{
+    m_required = b;
+}
+
+
+void
+NetInstallPage::onActivate()
 {
     ui->groupswidget->setFocus();
 }
diff --git a/src/modules/netinstall/NetInstallPage.h b/src/modules/netinstall/NetInstallPage.h
index 423c16b8e..58308412d 100644
--- a/src/modules/netinstall/NetInstallPage.h
+++ b/src/modules/netinstall/NetInstallPage.h
@@ -46,17 +46,24 @@ public:
 
     void onActivate();
 
-    bool isReady();
-
     // Retrieves the groups, with name, description and packages, from
     // the remote URL configured in the settings. Assumes the URL is already
     // in the global storage. This should be called before displaying the page.
     void loadGroupList();
 
+    // Sets the "required" state of netinstall data. Influences whether
+    // corrupt or unavailable data causes checkReady() to be emitted
+    // true (not-required) or false.
+    void setRequired( bool );
+    bool getRequired() const
+    {
+        return m_required;
+    }
+
     // Returns the list of packages belonging to groups that are
     // selected in the view in this given moment. No data is cached here, so
     // this function does not have constant time.
-    QList<PackageTreeItem::ItemData> selectedPackages() const;
+    PackageModel::PackageItemDataList selectedPackages() const;
 
 public slots:
     void dataIsHere( QNetworkReply* );
@@ -76,6 +83,7 @@ private:
     QNetworkAccessManager m_networkManager;
 
     PackageModel* m_groups;
+    bool m_required;
 };
 
 #endif // NETINSTALLPAGE_H
diff --git a/src/modules/netinstall/NetInstallViewStep.cpp b/src/modules/netinstall/NetInstallViewStep.cpp
index 347b2bf27..50e08486b 100644
--- a/src/modules/netinstall/NetInstallViewStep.cpp
+++ b/src/modules/netinstall/NetInstallViewStep.cpp
@@ -2,6 +2,7 @@
  *   Copyright 2016, Luca Giambonini <almack@chakraos.org>
  *   Copyright 2016, Lisa Vitolo <shainer@chakraos.org>
  *   Copyright 2017, Kyle Robbertze  <krobbertze@gmail.com>
+ *   Copyright 2017, Adriaan de Groot <groot@kde.org>
  *
  *   Calamares is free software: you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -30,11 +31,11 @@ CALAMARES_PLUGIN_FACTORY_DEFINITION( NetInstallViewStepFactory, registerPlugin<N
 NetInstallViewStep::NetInstallViewStep( QObject* parent )
     : Calamares::ViewStep( parent )
     , m_widget( new NetInstallPage() )
-    , m_nextEnabled( true )
+    , m_nextEnabled( false )
 {
     emit nextStatusChanged( true );
     connect( m_widget, &NetInstallPage::checkReady,
-             this, &NetInstallViewStep::nextStatusChanged );
+             this, &NetInstallViewStep::nextIsReady );
 }
 
 
@@ -126,7 +127,7 @@ NetInstallViewStep::onLeave()
     cDebug() << "Leaving netinstall, adding packages to be installed"
              << "to global storage";
 
-    QList<PackageTreeItem::ItemData> packages = m_widget->selectedPackages();
+    PackageModel::PackageItemDataList packages = m_widget->selectedPackages();
     QVariantList installPackages;
     QVariantList tryInstallPackages;
     QVariantList packageOperations;
@@ -138,7 +139,7 @@ NetInstallViewStep::onLeave()
         QVariant details( package.packageName );
         // If it's a package with a pre- or post-script, replace
         // with the more complicated datastructure.
-        if (!package.preScript.isEmpty() || !package.postScript.isEmpty())
+        if ( !package.preScript.isEmpty() || !package.postScript.isEmpty() )
         {
             QMap<QString, QVariant> sdetails;
             sdetails.insert( "pre-script", package.preScript );
@@ -156,14 +157,14 @@ NetInstallViewStep::onLeave()
     {
         QMap<QString, QVariant> op;
         op.insert( "install", QVariant( installPackages ) );
-        packageOperations.append(op);
+        packageOperations.append( op );
         cDebug() << "  .." << installPackages.length() << "critical packages.";
     }
     if ( !tryInstallPackages.empty() )
     {
         QMap<QString, QVariant> op;
         op.insert( "try_install", QVariant( tryInstallPackages ) );
-        packageOperations.append(op);
+        packageOperations.append( op );
         cDebug() << "  .." << tryInstallPackages.length() << "non-critical packages.";
     }
 
@@ -178,6 +179,11 @@ NetInstallViewStep::onLeave()
 void
 NetInstallViewStep::setConfigurationMap( const QVariantMap& configurationMap )
 {
+    m_widget->setRequired(
+        configurationMap.contains( "required" ) &&
+        configurationMap.value( "required" ).type() == QVariant::Bool &&
+        configurationMap.value( "required" ).toBool() );
+
     if ( configurationMap.contains( "groupsUrl" ) &&
             configurationMap.value( "groupsUrl" ).type() == QVariant::String )
     {
@@ -186,3 +192,10 @@ NetInstallViewStep::setConfigurationMap( const QVariantMap& configurationMap )
         m_widget->loadGroupList();
     }
 }
+
+void
+NetInstallViewStep::nextIsReady( bool b )
+{
+    m_nextEnabled = b;
+    emit nextStatusChanged( b );
+}
diff --git a/src/modules/netinstall/NetInstallViewStep.h b/src/modules/netinstall/NetInstallViewStep.h
index d9853f26f..ee53f61ce 100644
--- a/src/modules/netinstall/NetInstallViewStep.h
+++ b/src/modules/netinstall/NetInstallViewStep.h
@@ -60,6 +60,9 @@ public:
 
     void setConfigurationMap( const QVariantMap& configurationMap ) override;
 
+public slots:
+    void nextIsReady( bool );
+
 private:
     NetInstallPage* m_widget;
     bool m_nextEnabled;
diff --git a/src/modules/netinstall/PackageModel.h b/src/modules/netinstall/PackageModel.h
index 148bd99ab..06d6c0ca1 100644
--- a/src/modules/netinstall/PackageModel.h
+++ b/src/modules/netinstall/PackageModel.h
@@ -1,3 +1,4 @@
+
 /* === This file is part of Calamares - <http://github.com/calamares> ===
  *
  *   Copyright (c) 2017, Kyle Robbertze <kyle@aims.ac.za>
@@ -28,14 +29,13 @@
 
 #include <yaml-cpp/yaml.h>
 
-// Required forward declarations
-class PackageTreeItem;
-
 class PackageModel : public QAbstractItemModel
 {
     Q_OBJECT
 
 public:
+    using PackageItemDataList = QList< PackageTreeItem::ItemData >;
+
     explicit PackageModel( const YAML::Node& data, QObject* parent = nullptr );
     ~PackageModel() override;
 
@@ -52,7 +52,7 @@ public:
     QModelIndex parent( const QModelIndex& index ) const override;
     int rowCount( const QModelIndex& parent = QModelIndex() ) const override;
     int columnCount( const QModelIndex& parent = QModelIndex() ) const override;
-    QList<PackageTreeItem::ItemData> getPackages() const;
+    PackageItemDataList getPackages() const;
     QList<PackageTreeItem*> getItemPackages( PackageTreeItem* item ) const;
 
 private:
diff --git a/src/modules/netinstall/netinstall.conf b/src/modules/netinstall/netinstall.conf
index b87aef43e..f5977a267 100644
--- a/src/modules/netinstall/netinstall.conf
+++ b/src/modules/netinstall/netinstall.conf
@@ -1,2 +1,13 @@
 ---
+# This is the URL that is retrieved to get the netinstall groups-and-packages
+# data (which should be in the format described in netinstall.yaml).
 groupsUrl: http://chakraos.org/netinstall.php
+
+# If the installation can proceed without netinstall (e.g. the Live CD
+# can create a working installed system, but netinstall is preferred
+# to bring it up-to-date or extend functionality) leave this set to
+# false (the default). If set to true, the netinstall data is required.
+#
+# This only has an effect if the netinstall data cannot be retrieved,
+# or is corrupt: having "required" set, means the install cannot proceed.
+required: false